A footballer with a serious gambling problem has admitted accepting a £50,000 bribe to help throw a game in Britain.

According to a source familiar with the circumstances, the player – who has a Premiership club on his CV – racked up a £50,000 debt with a bookmaker. The bookmaker said he would write off the debt if the player got himself sent off and also persuaded three team-mates to get booked in a specific game.

The player agreed, and the incidents were fixed as requested. His team lostthe match, which was played in the past two years, the source said. The player subsequently sought professional help for his addiction, and was said to be "ashamed and full of remorse" about what happened. It is not known precisely how the bookmaker profited from the sending-off and bookings, but the assumption is that he either struck or laid "spread bets" relating to the cards, and that the game was at a level significant enough to warrant a sizeable market in this.

The suggestion that any match has been fixed – or that significant events within it have been rigged – is a nightmare scenario for football's authorities. It is confirmation that football in Britain is not immune to the corruption that has recently blighted other nations – including Italy, Germany and Poland – albeit with personal addiction as a driving force, as opposed to institutional corruption or large-scale criminal syndicates in those cases.

But addiction experts say it is illustrative of a wider gambling problem in society that raises issues for government as well as football's governing bodies.

The case was among a number of incidents disclosed privately by several sources at a seminar on gambling at the Sporting Chance clinic in Hampshire this week, seeking to highlight the threat of gambling to football's integrity. Those present included players and former players with personal experience of destructive behaviour caused by addiction.

Sporting Chance is Britain's foremost treatment centre for sports people with addictive illnesses. Its chief executive, Peter Kay, declined to confirm any specific details about the player who engineered the red card and who it is understood was treated at Sporting Chance.

Mr Kay said all the cases that the organisation handles were confidential. " Neither I nor Sporting Chance is responsible for what a client or ex-client might say, but if you're asking whether I'm aware of this case, the answer is yes," he said.

Pressed for further details about the "fixed" match, he said: " It doesn't matter if it is a Premiership player or a Conference player, quite frankly. It highlights that addiction of any sort can lead a person to take grave actions, possibly even attempt suicide."

One source at the seminar described a recent suicide attempt by a lower-division player who had a £37,000 gambling debt. Suicide attempts among problem gamblers are not unusual. Another source said they knew of current players – including some in the Premiership - who are fighting cocaine addiction without the knowledge of their clubs. There is an anecdotal link between cocaine and gambling among patients in rehab, according to Dr Henrietta Bowden Jones, one of the experts who addressed the seminar.

Dr Bowden Jones is a consultant psychiatrist and expert in substance misuse, and is the official spokesperson for the Royal College of Psychiatrists on matters pertaining to pathological gambling. She has worked with footballer addicts at a private London clinic, and has also referred players to Soprting Chance, founded by the former Arsenal player Tony Adams.

"You heard [in the seminar] from three speakers [all former players, unrelated to the "fix" case] about how lives and careers are destroyed, and how drastic decisions are made when someone is in the grip of addiction," said Mr Kay. "I don't believe the card business is widespread. But it has happened, yes, to my knowledge on several occasions."

Mr Kay first talked of an "epidemic" of gambling among footballers two years ago in an interview with The Independent. He stands by that description and has data to support it. In 2006, Sporting Chance dealt with about 30 footballers with addictive illnesses, gambling included. New referrals in the past year are twice that figure.

Mr Kay believes the increase is partly due to awareness of a problem within the game, and players' greater willingness to seek help. Though problem gambling is an issue for society at large, footballers seem to be disproportionately represented.

A government study last year – the 2007 Gambling Prevalence Survey – estimated that 0.6 per cent of Britain's adults are "problem gamblers" . That should equate to about 24 problem gamblers in English football among about 4,000 professionals. But experts believe the real figure could be 10 times that number, equivalent to two or three players per club.

Football's authorities have shown contrasting attitudes to gambling. In a survey of players conducted by The Independent in 2000 in association with the Professional Footballers' Association (PFA), more than a third of players said they bet on football, which at the time was against Football Association rules. Five players said they had been invited to "throw" a match, although all said they declined. But the FA subsequently relaxed its rules to outlaw bets only on games in which a player was involved, or could influence.

On the flip side, the FA is an active supporter – and funder – of programmes that educate players, especially young players, and provides help to those in trouble. The FA partially funds Sporting Chance, with the PFA the other major backer. No player has been declined treatment, and the provision of care for troubled players – paid for by the PFA and the FA – is not in doubt.

But there is intense debate about whether the game should take a concerted approach towards preventive education, using expert agencies. Within the Premier League, for example – the richest branch of football's family, and the league with the most to lose through any tarnishing of its image – there is a theoretical obligation to provide education, including on addiction, to young players. But in practice, central funding for specialist agency assistance remains largely untapped, and there are wide disparities about the level of education provided.

A wake-up call that games are being fixed might force the pace of change.